看到很多地方都说x86_64只有两个ring:ring 0和ring 3
比如:
1、 http://wiki.osdev.org/Security 提到"However, many architectures have only two rings (e.g. x86_64), corresponding to ring 0 and 3 in this description."
2、Prentice.Hall.The.Definitive.Guide.to.the.Xen.Hypervisor.Nov.2007.pdf 一本讲虚拟化的书
1.7.1 The Hypervisor, the OS, and the Applications 提到 When AMD tidied up the IA32 architecture as part of the process of creating x86-64, one of the things it did was reduce the number of rings.
但是我翻遍了 《Intel 64 and IA_32 Architectures Software Developer's Manual》也没有找到说x86_64只有2个ring的地方
However, many architectures have only two rings (e.g. x86_64), corresponding to ring 0 and 3 in this description."
However, many architectures have only two rings (e.g. x86_64), corresponding to ring 0 and 3 in this description."
x86 has ring 0,1,2,3, but for portable, linux (windows too) just use two: ring 0 & ring 3.
good luck作者: sanbiangongzi 时间: 2012-05-24 09:06 回复 4# folklore
However, many architectures have only two rings (e.g. x86_64), corresponding to ring 0 and 3 in this description.
x86 has ring 0,1,2,3, but for portable, linux (windows too) just use two: ring 0 & ring 3.